This article originally appeared in the August 2010 issue of INTERNET TELEPHONY.

As wireless moves to 4G, Wi-Fi technology will dominate. 

LTE and WiMAX (News - Alert) will remain robust markets, but more wireless broadband bits will be carried by Wi-Fi technology than by LTE and WiMAX combined. What’s more, Wi-Fi technology will come to dominate both cellular backhaul and fixed wireless broadband services wherever direct fiber connections remain expensive.

The WiFi (News - Alert) market has enormous diversity and openness, which drives innovation. As a result, WiFi leads in deployment of 4G technologies like OFDM, MIMO and beamforming, while WiFi market growth has produced high volume and low prices for Wi-Fi silicon. Today, WiFi silicon is being adapted for both unlicensed and licensed wireless devices, and these devices are being adopted rapidly by fixed wireless ISPs.

But the big impact will be in mobile wireless broadband where WiFi will beat out femtocells to carry the bulk of wireless broadband bits. Femtocells (News - Alert) are tiny mobile cell sites using the mobile operators' licensed spectrum, supporting all handsets and all services. Femtocells are a great way to extend coverage, but mobile operators’ problem is data capacity, where WiFi wins for many reasons.

First, most mobile data is destined for the open Internet, not for someplace on the mobile operator's network. Meanwhile, the mobile operator's network is complex – designed to support differential services and fine-grained billing, so it’s significantly more expensive than a best-effort network. Yet operators can’t charge for this extra capability when people just want to get to the Internet.

Most mobile data demand is from computers and smart phones. Laptops have Wi-Fi, as do newer smartphones; thus, the only potential disadvantage of WiFi is rapidly vanishing.

Wi-Fi access points cost less than femtocells. Besides being somewhat simpler, they are being produced in very high volumes, far higher than mobile operators are likely to achieve with femtocells, and Wi-Fi hotspots are showing up everywhere.

Individuals spend most of their online time in just two locations: home and the office. Enterprises will not install femtocells that the IT department can't control. Consumers, retail and public locations are already doing WiFi. They won't install femtocells unless there is some form of subsidy from the operator – another cost with no net benefit. 

In the end, mobile operators will encourage WiFi offload by bundling "free" public WiFi access with their mobile data plans. Thus, in the future, most mobile data bytes will go over Wi-Fi, while the 3G and 4G networks provide backup when no WiFi is available. Mobile operators’ path to success is to focus on facilitating anywhere connectivity for their customers regardless of the technology involved.

So LTE (News - Alert) and WiMAX are great, but WiFi technology will carry the load.